Optical recording method and apparatus using two fight spots
US4841514A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 16, 1986 |
| Grant date | Jun 20, 1989 |
| Priority date | — |
| Expiry date | Oct 16, 2006 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B7/125
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A light spot determining a first condition that an optical recording medium is cooled after being heated to a temperature exceeding a first temperature and a light spot determining a second condition that the optical recording medium is cooled after being heated to a temperature exceeding a second temperature higher than the room temperature and not exceeding the first temperature higher than the second temperature, namely, the two light spots are radiated onto the optical recording medium and in the same guide track thereof wherein signals are recorded and erased on the optical recording medium by controlling the spot diameter of each light spot and/or the light intensity thereof.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.